IMAGE ENCODER AND IMAGE ENCODING METHOD, IMAGE DECODER AND IMAGE DECODING METHOD, AND IMAGE PROCESSOR AND IMAGE PROCESSING METHOD

摘要

In an ADRC processing, an image is divided into blocks, and the maximum value MAX and the minimum value MIN of the pixel values of each block are detected and the local dynamic range of each block is determined by the equation DR=MAX-MIN. The minimum value MIN is subtracted from the pixel values of each block, and the remainders are divided by DR/2 to obtain the result of the ADRC processing. The result is used as an object of various editing procedures which may be substantially identical with those when the original image, not subjected to the ADRC processing, is directly edited. The edition load can be reduced as compared with the edition of the original image, because the amount of data of the ADRC processing result is small. Hence the image processing is performed efficiently.